Best way to invest with leverage?

Altruists who don’t care too much about risk (and young people in general) should plausibly use leveraged investing. What’s the best way to get leverage?

  1. Margin borrowing seems like the default solution. I might try it if there’s nothing better.

  2. Theoretically options could be used, but I’m unsure whether they work in practice.

  3. Supposedly futures offer massive leverage, but I haven’t explored the details, and they seem hard to trade yourself. I’d like something I can just buy and hold for a long time.

  4. Something else?

Ideally, there should be a fund that you just buy into to get leverage, with someone else handling the details. But leveraged ETFs don’t work because they’re optimized for day trading and as a result lose money for buy-and-hold investors.